Fix an infinite loop bug in DAG Combine about keeping transfering between ANY_EXTEND and SIGN_EXTEND.
llvm-svn: 206873
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index cdf1aed..a52dacf 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -5479,7 +5479,10 @@
}
if (N0.getOpcode() == ISD::SETCC) {
- // aext(setcc) -> sext_in_reg(vsetcc) for vectors.
+ // For vectors:
+ // aext(setcc) -> vsetcc
+ // aext(setcc) -> truncate(vsetcc)
+ // aext(setcc) -> aext(vsetcc)
// Only do this before legalize for now.
if (VT.isVector() && !LegalOperations) {
EVT N0VT = N0.getOperand(0).getValueType();
@@ -5494,19 +5497,14 @@
cast<CondCodeSDNode>(N0.getOperand(2))->get());
// If the desired elements are smaller or larger than the source
// elements we can use a matching integer vector type and then
- // truncate/sign extend
+ // truncate/any extend
else {
- EVT MatchingElementType =
- EVT::getIntegerVT(*DAG.getContext(),
- N0VT.getScalarType().getSizeInBits());
- EVT MatchingVectorType =
- EVT::getVectorVT(*DAG.getContext(), MatchingElementType,
- N0VT.getVectorNumElements());
+ EVT MatchingVectorType = N0VT.changeVectorElementTypeToInteger();
SDValue VsetCC =
DAG.getSetCC(SDLoc(N), MatchingVectorType, N0.getOperand(0),
N0.getOperand(1),
cast<CondCodeSDNode>(N0.getOperand(2))->get());
- return DAG.getSExtOrTrunc(VsetCC, SDLoc(N), VT);
+ return DAG.getAnyExtOrTrunc(VsetCC, SDLoc(N), VT);
}
}